Electric locomotive.



J. LE C. DAVIS.

ELECTRIC LOCOMOTIVE.

APPLICATION FILED AUGJ, 19H.

Patented June 13, 1916.

A'TTORNEY.

UNITED STATES PATENT OFFICE.

JOSEPH LE CONTE DAVIS, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 WESTING- HOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

ELECTRIC LOCOMOTIVE.

Application filed August 7,

To all whom it may concern:

Be it known that I, JosnrH LE C. DAVIS, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electric Locomotives, of which the following is a specification.

My invention relates to railway locomotives and it has special reference to such locomotives as are propelled by electric motors.

One of the objects of my invention is to provide a motor unit that shall be specially compact and capable of developing very large power, and also to provide a simple and advantageous driving connection between the motor unit and the driving wheels of the locomotive in which the driving strains are particularly well distributed while, at the same time, the rotating elements of the motor unit are adapted to opcrate at a relatively high speed.

Another object of my invention is to pro vide a locomotive having a driving unit that is relatively light in weight per unit of power, and particularly adapted for high speed and heavy service by reason of its peculiar construction which also permits of great economy in lateral space for gearing and driving connections which may be utilized for longer and more powerful motors.

A still further object of my invention is to simplify and improve the construction and operation of driving units of the above indicated character, and to provide a unit that shall be compact and rugged in construction, eflicient and powerful in operation, and particularly adapted by reason of its general arrangement of parts, for the kind of service contemplated.

It is generally understood that a single large motor may be constructed more cheaply than two or more small motors for developing the same amount of power with the same speed. In the case of very large units, however, it is found that several small motors can be constructed more cheaply than one large motor for doing the same work.

According to my present invention, I provide a particularly advantageous motor unit which, to a certain degree, combines the ad vantages usually obtained by using either Specification of Letters Patent.

Patented June 13, 1916.

Serial No. 642,879.

several small motors or one large motor, and comprises a plurality of small armatures that are symmetrically distributed relative to a centrally located countershaft to which they are geared and a unitary field structure comprising a plurality of similar main field core members and auxiliary field members equal in number to the armatures.

It will be evident to those skilled in the art that such a driving unit is especially adapted for high speed and heavy locomotive service for the reason that the usual limitations as to safe peripheral speed of the armatures are not encountered on account of the greatly reduced size of the several armatures employed; consequently, much greater power and linear speed may be attained per unit of weight than with a single large driving motor. Also the width of the gearing may be materially reduced over that necessary for a single driving motor because of the fact that the total power is transmitted to the gearing equally at four points instead of at a single point. Hence, the motors may be made longer and more powerful.

I prefer to mount the motor unit on the locomotive frame or body and to establish an operative connection from the countershaft of the unit to the driving wheels by means of side rods.

Figure 1 of the accompanying drawing is a diagrammatic elevation of a portion of a locomotive embodying my invention. Figs. 2 and 3 are detail views, on a larger scale, of parts of the motor unit shown in Fig. 1.

Referring to the drawings, the locomotive here shown comprises a frame 1, driving wheel axles 3 and 4, a countershaft 2, and a motor unit 5 which is operatively connected to the countershaft.

The motor unit 5 is mounted on the frame 1 of the locomotive which, as usual, is a spring-borne part. The motor unit 5 comprises a central countershaft 6, a gear wheel 7 secured thereto, a plurality of motor armatures 8, 9, 10 and 11 that are symmetrically disposed relative to the countershaft 6 and are operatively connected thereto by means of pinions 12 which mesh with the gear wheel 7; and field core members 13, 14, 15 and 16 that are located between the armatures and complete a single magnetic circuit as follows: from field member 13 through the parts, 9, ll, 10, 15, 11, 16 and 8, the usual air gaps being included between the armatures and field members. Each of the field members provided with a single field coil i-O which is located midway between the adjacent armatures ot the motor unit. The field members are supported by a central spider 21. and by nonanagnetizable brackets 93 which are clearly shown in Figs. 2 and The arms .22 or the spider 21 constitute the auxiliary interpolar field members of the unit and may be provided with auxiliary coils 20.

Since the armatures are symmetrically disposed about the countershatt 6, the strains on the eountershatt bearings are largely equalized and the operation of the locomotive is improved. Furthermore, the arrangement is specially well adapted for utilizing armatures which operate at high speeds and which are therefore relatively small and cheap to manufacture. The countershatt (3 is operatively connected to the countershaft 2 by means of side rods 17 while side rods 18 and 19 complete the driving connection between the countershaft 2 and the driving wheel axles 3 and l.

It will be observed that the number of field coils does not exceed the number of armatures and that the field structure, as a whole, is relatively simple, so that the cost of manufacturing the unit is relatively small. Furthermore, the supporting structure constitutes the auxiliary field members of the machine which are also equal in number to the armatures.

A compensating winding 25 may be used in addition to the auxiliary coinmutating coils 20 in which case the coils of the winding are preferably located in slots 26 provided in the pole faces in a well known manner. as shown in Fig. 2. In order to reduce the size of the coils which constitute the compensating winding and not to interfere with the removal of any of the armatures, parts of each coil are placed in the slots of adjacent pole faces rather than in opposed pole faces.

I prefer to make duplicate driving connections on the two sides of the locon'iotive in the usual manner, although only one side is illustrated.

Other modifications may be effected within the spirit of my invention.

I claim as my invention:

1. A dynamo-electric machine comprising a plurality of symmetrically disposed armatures, interposed field magnet members and a plurality of members corresponding in number and location to said armatures for supporting said field magnet members.

2. A dynamo-electric machine comprising a plurality of symmetrically disposed armatures, interposed field magnet members and a stationary spider centrally disposed with respect to said armaturcs and said field magnet members and having a plurality of arms disposed in radial lines with said armatures and adapted to support said field magnet members.

3. A dynan'io-electric machine comprising a plurality of symmetrically disposed armatures, interposed field magnet members, a stationary snider centrally disposed with respect to said armatures and said field magnet members and having a plurality of magnetizable projections disposed in radial relation with said armatures and field magnet windings associated with said field ma not members and said magnetizable projections.

4. A motor unit comprising a centrally located countershait. a stationary spider concentric therewith and having a plurality of radial arms, a plurality of armatures synnnetrically disposed relative to the countershaft in a radial line with said arms and geared to said shaft. and interposed field members between the armatiu'es and supported by said radial arms.

41A motor unit comprising a central counter-shaft, a plurality of armatures symmetrically disposed relative to the countershai t and geared thereto, interposed field members, and a central stationary spider concentric with the countersha't't and having a plurality of radial arms corresponding in number and location to the armatures for supporting said field men'ibers.

($.11 motor unit comprising a central counter-shaft, a plurality of armatures symmetri *ally disposed relative to the countershal t and geared thereto, interposed field members. a central stationary spider concentric with the countershatt and having a plurality ol radial arms corresponding in number and location to the armatures and non-magnetizable supporting members cooperating with said arms ior supporting said field members.

7. A motor unit comprising a central counter-shaft, a plurality of armatures symmetrically disposed relative to the countershait and geared thereto, interposed field members, a central statiomiry spider concentric with the countershatt and having a plurality of radial magnetizable arms corresponding in number and location to the armatures and provided with auxiliary field magnet windings, and nonanagnetizable supporting members between the main and auxiliary field magnet members.

8. In a motor unit, the combination with a plurality of symmetrically disposed armatures, and field magnet members and windings therefor severally disposed intermediate said armatures, of radially projecting arms disposed intermediate said field magnet members, and oppositely projecting members associated with said arms for supintermediate said field magnet members,

and oppositely projecting members of nonmagnetizable material associated with said arms for supporting said field magnet members in position.

10. In a motor unit, the combination witha plurality of symmetrically disposed armatures and field magnet members having main field windings severally disposed intermediate said armatures and serving to produce magnetic flux in each of the adjacently located armatures, of a plurality of compensating windings severally surrounding each of said field magnet members and adapted to act in conjunction with the adjacently located armatures.

11. In a motor unit, the combination with a plurality of armatures and field magnet members severally disposed intermediate thereof, of main field windings for each field magnet member, and compensating windings surrounding each field magnet member and serving in common for said armatures.

12. In a motor unit, the combination with a plurality of armatures, and field magnet members having field magnet windings therefor, of con'ipensating windings surrounding aeh main field magnet member and serving in common for each adj acently located armature and auxiliary field magnet members and windings disposed intermediate said main field magnet members.

13. In a motor unit, the combination with a centrally located countershaft, a plurality of symmetrically disposed armatures, a plurality of radially disposed arms severally projecting outwardly in line with the aXes of said armatures, and a plurality of main field magnet members severally disposed intermediate said armatures and supported by said arms, of main field windings and compensating windings surrounding each field magnet member, and auxiliary field windings severally disposed on said radial arms.

14:. In a motor unit, the combination with a counter-shaft, a plurality of armatures symmetrically disposed relative thereto, mechanical means operatively associated with said armatures and said counter-shaft, and field magnet members severally disposed between said armatures, of main field coils for said field members, and compensating windings disposed around each field memher and serving in common for said armatures.

15. In a motor unit, the combination with a plurality of armatures, and field magnet members therefor, of compensating windings surrounding each field magnet member and serving in common for a plurality of arn'iatures. I

16. The combination with a plurality of motor armatures, and a field magnet member disposed between them and serving in common for both armatures, of a compensating winding associated with said field magnet member and serving both armatures in common.

17. In a motor unit, the combination with a plurality of armatures and field magnet members therefor, of compensating windings associated with each field magnet member and serving in common for a plurality of armatures and a single commutating polar projection for each armature.

18. The combination with a plurality of symmetrically disposed motor armatures and a plurality of field magnet members severally disposed between the adjacent armatures and serving in common said adjacent armatures, of a compensating winding associated with each of said field magnet members and serving the said adjacent armatures in common and a plurality of commutating polar projections severally disiposed in cooperative relation to said armatures.

In testimony whereof, I have hereunto subscribed my name this 31st day of July,

JOSEPH LE CONTE DAVIS. Witnesses J. B. Gaosswnen, B. B. HINns.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

